/* ============================================================
   Ahsen Tahir: academic site
   Single stylesheet, no build step, no JS.
   ============================================================ */

/* Dark theme, committed: the site renders dark regardless of the reader's
   OS setting. The print block at the bottom flips back to black-on-white so
   Cmd-P on the CV still produces a normal printable page. */

:root {
  --bg:            #14171a;
  --bg-subtle:     #1c2024;
  --text:          #e3e7ea;
  --text-muted:    #a3adb6;
  --text-faint:    #79838c;
  --link:          #7cc4dd;
  --link-hover:    #a8dcef;
  --rule:          #282e33;
  --rule-strong:   #394147;
  --accent:        #7cc4dd;

  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue",
               Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;

  --measure: 42rem;      /* readable line length for body copy */
  --sidebar: 15rem;
  --gap: 3rem;
}

/* Tell the browser the page is dark, so form controls, scrollbars and the
   address bar on mobile match instead of flashing white. */
:root { color-scheme: dark; }

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* ---------- links ---------- */

a { color: var(--link); text-decoration: none; }
a:hover { color: var(--link-hover); text-decoration: underline; }

/* ---------- top navigation ---------- */

.masthead {
  border-bottom: 1px solid var(--rule);
  background: var(--bg);
  position: sticky;
  top: 0;
  z-index: 20;
}

.masthead-inner {
  max-width: 68rem;
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
  min-height: 3.5rem;
}

.site-name {
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
  letter-spacing: -0.01em;
  padding: 0.75rem 0;
  white-space: nowrap;
}
.site-name:hover { color: var(--text); text-decoration: none; }

.site-nav {
  display: flex;
  gap: 1.4rem;
  flex-wrap: wrap;
  align-items: center;
  padding-bottom: 0.25rem;
}

.site-nav a {
  color: var(--text-muted);
  font-size: 0.94rem;
  padding: 0.75rem 0;
  border-bottom: 2px solid transparent;
}
.site-nav a:hover { color: var(--text); text-decoration: none; }
.site-nav a[aria-current="page"] {
  color: var(--text);
  border-bottom-color: var(--accent);
  font-weight: 600;
}

/* ---------- page frame ---------- */

.page {
  max-width: 68rem;
  margin: 0 auto;
  padding: 2.75rem 1.5rem 4rem;
  display: grid;
  grid-template-columns: var(--sidebar) minmax(0, 1fr);
  gap: var(--gap);
  align-items: start;
}

/* ---------- author sidebar ---------- */

.sidebar { position: sticky; top: 5rem; }

.avatar {
  width: 8.5rem;
  height: 8.5rem;
  border-radius: 50%;
  object-fit: cover;
  display: block;
  margin-bottom: 1rem;
  border: 1px solid var(--rule);
}

.sidebar h2 {
  font-size: 1.05rem;
  margin: 0 0 0.4rem;
  letter-spacing: -0.01em;
}

.sidebar .bio {
  font-size: 0.85rem;
  line-height: 1.5;
  color: var(--text-muted);
  margin: 0 0 1rem;
}

.sidebar-links {
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 0.85rem;
  line-height: 1.45;
}

.sidebar-links li {
  display: flex;
  gap: 0.6rem;
  align-items: flex-start;
  margin-bottom: 0.55rem;
  color: var(--text-muted);
}

.sidebar-links .ico {
  flex: 0 0 0.9rem;
  display: flex;
  justify-content: center;
  color: var(--text-faint);
  /* nudge the icon down onto the first text line's optical centre */
  padding-top: 0.32em;
}

.sidebar-links .ico svg { display: block; }

/* ---------- main content ---------- */

.content { min-width: 0; }
.content > *:first-child { margin-top: 0; }

.content p,
.content ul,
.content ol { max-width: var(--measure); }

h1 {
  font-size: 1.9rem;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin: 0 0 1.25rem;
}

h2 {
  font-size: 1.3rem;
  letter-spacing: -0.01em;
  margin: 2.75rem 0 0.9rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--rule);
}

h3 {
  font-size: 1.05rem;
  margin: 1.75rem 0 0.5rem;
}

p { margin: 0 0 1.05rem; }

/* opening paragraph: slightly larger, sets the frame before the detail */
.lede {
  font-size: 1.12rem;
  line-height: 1.55;
  color: var(--text);
  margin-bottom: 1.15rem;
}

ul, ol { padding-left: 1.25rem; margin: 0 0 1.05rem; }
li { margin-bottom: 0.45rem; }

strong { font-weight: 650; }

hr {
  border: 0;
  border-top: 1px solid var(--rule);
  margin: 2.5rem 0;
}

code {
  font-family: var(--font-mono);
  font-size: 0.87em;
  background: var(--bg-subtle);
  padding: 0.1em 0.35em;
  border-radius: 3px;
}

/* ---------- publication entries ---------- */

.pub {
  padding: 1.15rem 0;
  border-bottom: 1px solid var(--rule);
  max-width: var(--measure);
}
.pub:last-child { border-bottom: 0; }

.pub-title {
  display: block;
  font-weight: 650;
  line-height: 1.4;
  margin-bottom: 0.35rem;
  color: var(--text);
}
a.pub-title:hover { color: var(--link); }

.pub-authors {
  display: block;
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 0.2rem;
}
.pub-authors .me { color: var(--text); font-weight: 650; }

.pub-venue {
  display: block;
  font-size: 0.9rem;
  font-style: italic;
  color: var(--text-muted);
  margin-bottom: 0.45rem;
}

.pub-links {
  font-size: 0.88rem;
  color: var(--text-faint);
}
.pub-links a { margin-right: 0.15rem; }
.pub-links .sep { margin: 0 0.4rem; }

.pub-excerpt {
  font-size: 0.94rem;
  color: var(--text-muted);
  margin: 0.5rem 0 0.55rem;
}

/* ---------- venue badge (accepted papers) ---------- */

.badge {
  display: inline-block;
  font-size: 0.72rem;
  font-style: normal;   /* .pub-venue is italic; the badge should not inherit it */
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
  border: 1px solid var(--accent);
  border-radius: 3px;
  padding: 0.1rem 0.42rem;
  margin-right: 0.5rem;
  vertical-align: 1px;
  white-space: nowrap;
}

/* ---------- keyword tags ---------- */

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0.85rem 0 0;
  padding: 0;
  list-style: none;
}

.tags li {
  margin: 0;
  font-size: 0.78rem;
  line-height: 1.4;
  color: var(--text-muted);
  border: 1px solid var(--rule);
  background: var(--bg-subtle);
  border-radius: 100px;
  padding: 0.2rem 0.65rem;
  white-space: nowrap;
}

/* subtitle under a project/paper title */
.pub-subtitle {
  display: block;
  font-size: 0.95rem;
  color: var(--text);
  margin-bottom: 0.5rem;
}

/* ---------- project cards ---------- */

.projects {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr));
  gap: 1.5rem;
  max-width: 100%;
  margin-bottom: 1.5rem;
}

.project {
  border: 1px solid var(--rule);
  border-radius: 6px;
  overflow: hidden;
  background: var(--bg);
  display: flex;
  flex-direction: column;
}

.project img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  display: block;
  border-bottom: 1px solid var(--rule);
  background: var(--bg-subtle);
}

.project-body { padding: 1rem 1.1rem 1.15rem; }

.project h3 { margin: 0 0 0.45rem; font-size: 1rem; line-height: 1.4; }

.project p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin: 0 0 0.6rem;
  max-width: none;
}

.project .stack {
  font-size: 0.8rem;
  color: var(--text-faint);
  font-family: var(--font-mono);
  line-height: 1.5;
  margin-bottom: 0.6rem;
}

.project .links { font-size: 0.88rem; }

/* ---------- CV ---------- */

.cv-entry { margin-bottom: 1.5rem; max-width: var(--measure); }

.cv-entry .role {
  font-weight: 650;
  display: block;
  line-height: 1.45;
}

.cv-entry .meta {
  font-size: 0.88rem;
  color: var(--text-muted);
  display: block;
  margin-bottom: 0.4rem;
}

.cv-entry ul { margin-top: 0.4rem; margin-bottom: 0; }
.cv-entry li { font-size: 0.95rem; }

.btn {
  display: inline-block;
  border: 1px solid var(--rule-strong);
  border-radius: 5px;
  padding: 0.5rem 1rem;
  font-size: 0.92rem;
  color: var(--text);
  background: var(--bg-subtle);
}
.btn:hover {
  text-decoration: none;
  border-color: var(--accent);
  color: var(--accent);
}

/* ---------- news list ---------- */

.news { list-style: none; padding: 0; max-width: var(--measure); }
.news li {
  padding-left: 0;
  margin-bottom: 0.7rem;
  font-size: 0.96rem;
}
.news .date {
  font-weight: 650;
  color: var(--text);
}

/* ---------- callout ---------- */

.note {
  border-left: 3px solid var(--rule-strong);
  padding: 0.15rem 0 0.15rem 1rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  margin: 1.5rem 0;
  max-width: var(--measure);
}

/* ---------- footer ---------- */

.site-footer {
  border-top: 1px solid var(--rule);
  margin-top: 1rem;
  padding: 1.75rem 1.5rem 2.5rem;
  font-size: 0.85rem;
  color: var(--text-faint);
}
.site-footer .inner { max-width: 68rem; margin: 0 auto; }
.site-footer a { color: var(--text-muted); }

/* ---------- responsive ---------- */

@media (max-width: 56rem) {
  .page {
    grid-template-columns: 1fr;
    gap: 2rem;
    padding-top: 2rem;
  }
  .sidebar {
    position: static;
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 0 1.25rem;
    align-items: start;
    padding-bottom: 1.75rem;
    border-bottom: 1px solid var(--rule);
  }
  .avatar { width: 6rem; height: 6rem; grid-row: span 3; margin-bottom: 0; }
  .sidebar h2 { align-self: end; }
  .masthead { position: static; }
}

@media (max-width: 34rem) {
  body { font-size: 16px; }
  h1 { font-size: 1.6rem; }
  .sidebar { grid-template-columns: 1fr; }
  .avatar { grid-row: auto; margin-bottom: 0.85rem; }

  /* compact header: the nav wraps to a second row here, so drop the
     desktop min-height and vertical padding that would double-space it */
  .masthead-inner {
    padding: 0.5rem 1rem 0.6rem;
    min-height: 0;
    gap: 0 1rem;
  }
  .site-name { padding: 0.25rem 0; }
  .site-nav { gap: 0.25rem 1rem; padding-bottom: 0; }
  .site-nav a { font-size: 0.88rem; padding: 0.2rem 0; }

  .page { padding: 1.5rem 1rem 3rem; }
}

/* ---------- print (so Cmd-P on /cv gives a usable PDF) ---------- */

@media print {
  /* Re-point the palette to ink-on-paper. Doing it at the token level means
     every rule below inherits it; otherwise the dark --text would print as
     pale grey on white and the CV would be unreadable. */
  :root {
    --bg:          #fff;
    --bg-subtle:   #fff;
    --text:        #000;
    --text-muted:  #222;
    --text-faint:  #444;
    --link:        #000;
    --link-hover:  #000;
    --rule:        #bbb;
    --rule-strong: #999;
    --accent:      #000;
    color-scheme: light;
  }

  .masthead, .site-footer, .sidebar, .btn { display: none !important; }
  .page { display: block; max-width: none; padding: 0; }
  body { font-size: 11pt; color: #000; background: #fff; }
  a { color: #000; text-decoration: none; }
  .content p, .content ul, .content ol, .cv-entry, .pub { max-width: none; }
  h2 { margin-top: 1.2rem; }
  .pub { break-inside: avoid; }
  .cv-entry { break-inside: avoid; }
}